\(\textbf {Waymo Open Dataset}\) . The Waymo Open Dataset [1]} is a recently released large-scale autonomous driving dataset, which consists of total 798 training sequences with around 158,361 LiDAR samples, and 202 validation sequences with 40,077 LiDAR samples. Following the popular point cloud detection codebase OpenPCDet [2]}, we subsample a single frame of 20% data (about 32k frames) of all the training samples as the training set. It annotated the objects in the full 360\(^{\circ }\)  field. The official evaluation metrics of Waymo are mean average precision (AP) and mean average precision weighted by heading (APH) in difficulty levels (L1 and L2).
